#!/bin/sh /etc/rc.common

USE_PROCD=1
START=96
STOP=10

extra_command "hot_reload" "Hot-reload service"

CONF="honk"
PROG="/usr/bin/honk-core"
# honk-core hardcodes dae-compatible datapath names (dae0/dae0peer + daens);
# these are the real interface/netns names, not leftover dae config.
HONK_HOST_IFACE="dae0"
HONK_PEER_IFACE="dae0peer"
HONK_NETNS_NAME="daens"
HONK_NETNS_PATH="/run/netns/$HONK_NETNS_NAME"
RESOLV_HONK="/tmp/resolv.conf.honk"

set_chmod_640() {
    mkdir -p /etc/honk/config.d /etc/honk/state /var/log/honk
    chmod -R u=rwX,go= /etc/honk 2>/dev/null || true
    chmod 700 /etc/honk /etc/honk/config.d /etc/honk/state 2>/dev/null || true
}

cleanup_netns() {
    ip netns del "$HONK_NETNS_NAME" 2>/dev/null || true
    umount "$HONK_NETNS_PATH" 2>/dev/null || true
    rm -f "$HONK_NETNS_PATH" 2>/dev/null || true
    ip link del "$HONK_HOST_IFACE" 2>/dev/null || true
    ip link del "$HONK_PEER_IFACE" 2>/dev/null || true
}

hijack_resolv_conf() {
    grep -q ' /tmp/resolv\.conf ' /proc/mounts && return 0

    local dns_list WANS
    . /lib/functions/network.sh
    unset -v __NETWORK_CACHE
    __network_ifstatus WANS "" "[@.route[@.target='0.0.0.0' && !@.table]].interface" 2>/dev/null
    set -- $WANS

    if [ $# -eq 1 ]; then
        dns_list=$(ubus call "network.interface.$1" status 2>/dev/null | \
            jsonfilter -e '@["dns-server"][*]' 2>/dev/null)
        if [ -z "$dns_list" ] && [ -f "/tmp/resolv.conf.d/resolv.conf.auto" ]; then
            dns_list=$(awk '/^nameserver/{print $2}' "/tmp/resolv.conf.d/resolv.conf.auto")
        fi
    fi

    [ -z "$dns_list" ] && dns_list="119.29.29.29 223.5.5.5"

    [ -f /tmp/resolv.conf ] || touch /tmp/resolv.conf
    grep -E '^(search|domain) ' /tmp/resolv.conf > "$RESOLV_HONK" 2>/dev/null

    for dns in $dns_list; do
        echo "nameserver $dns" >> "$RESOLV_HONK"
    done

    mount --bind "$RESOLV_HONK" /tmp/resolv.conf
    mount -o remount,ro,bind /tmp/resolv.conf
}

restore_resolv_conf() {
    while grep -q ' /tmp/resolv\.conf ' /proc/mounts; do
        mount -o remount,rw,bind /tmp/resolv.conf 2>/dev/null
        umount /tmp/resolv.conf 2>/dev/null || break
    done
    rm -f "$RESOLV_HONK"
}

start_service() {
    local enabled config_file

    config_load "$CONF"
    config_get_bool enabled "config" "enabled" "0"
    [ "$enabled" -eq "1" ] || return 1

    config_get config_file "config" "config_file" "/etc/honk/config.dae"

    if [ ! -x "$PROG" ]; then
        logger -t honk "not starting: $PROG is missing or not executable"
        return 1
    fi

    set_chmod_640
    cleanup_netns
    hijack_resolv_conf

    procd_open_instance "$CONF"
    # mimalloc pre-reserves a 1 GiB arena; VSZ only, but it dwarfs the real
    # footprint in ps. MIMALLOC_ARENA_RESERVE=0: grow on demand instead.
    procd_set_param env DAE_LOCATION_ASSET="/usr/share/v2ray" MIMALLOC_ARENA_RESERVE="0"
    procd_set_param command "$PROG" --config "$config_file"
    procd_set_param netdev "$HONK_HOST_IFACE" "$HONK_PEER_IFACE"
    procd_set_param limits core="unlimited"
    procd_set_param limits nofile="1000000 1000000"
    procd_set_param term_timeout 8
    procd_set_param respawn 3600 5 5
    procd_set_param stderr 1
    procd_close_instance
}

service_stopped() {
    restore_resolv_conf
    cleanup_netns
}

reload_service() {
    stop
    start
}

service_triggers() {
    procd_add_reload_trigger "$CONF"
}

hot_reload() {
    set_chmod_640
    if /etc/init.d/honk running; then
        "$PROG" reload
    else
        start
    fi
}